Laryngoscopes comprise insertion sections, which are the elongate part of a laryngoscope which extends towards and into a patient's oral cavity during intubation. Insertion sections may be removably attachable to a laryngoscope body, integral parts of laryngoscopes or themselves function as laryngoscopes. As well as an insertion section, laryngoscopes typically comprises a handle which is usually elongate and which may be arranged at an angle to the proximal end of the insertion section or generally parallel to the proximal end of the insertion section, or at any angle therebetween. Some known laryngoscope insertion sections, such as Miller or Wisconsin insertion sections, are substantially flat. However, the insertion section of a laryngoscope is more commonly bent to better enter through a patient's oropharynx towards their larynx. Some known insertion sections include first and second straight portions, with a bend therebetween, or are curved, at least in part. Within this specification and the appended claims, the inferior surface is the surface of an insertion section which faces the patient's tongue in use.
The opposite surface is referred to as the superior surface. Words such as inferior, inferiorly, superior and superiorly are used in corresponding senses. A superior-inferior axis is a virtual axis extending parallel to the superior and inferior directions. The words distal and distally refer to being towards the end of the insertion section which extends towards a patient's trachea in use and the words proximal and proximally refer to being towards the person carrying out intubation in use.
It is known to provide a laryngoscope insertion section including a tube guide which extends along the length of the insertion section. For example, WO 04/073510 (Gandarias) discloses a laryngoscope insertion section including a tube guide which extends laterally from an elongate member which contains apparatus to provide an image of a patient's larynx in use. The tube guide has inferior and superior walls which extend continuously along the length of the tube guide. An endotracheal tube may be fitted into the tube guide and the insertion of the endotracheal tube into a patient's larynx can be viewed by a user. The endotracheal tube can then be detached from the insertion section whilst the insertion section remains within a patient and the insertion section can be removed, leaving the endotracheal tube in place.
Tube guides can facilitate intubation by ensuring that, once an insertion section is in place and the patient's larynx sighted, an endotracheal tube is already in the correct location to be pushed forward and inserted into a patient's larynx. However, a potential disadvantage is that tube guides increase the bulk of the insertion section. Accordingly, the present invention aims to provide an insertion section with a tube guide in which the insertion section is adapted to reduce its bulk, to facilitate introduction of the insertion section into a patient with an endotracheal tube in place within the tube guide.
Another problem with known insertion sections with tube guides is that they are typically designed for use with endotracheal tubes of a limited range of sizes. Some aspects of the present invention are directed to providing insertion sections adapted to guide a wider operating range of endotracheal tube sizes than known insertion sections with tube guides.
Furthermore, the laryngoscope disclosed in WO 04/073510 has a generally J-shaped insertion section which retains an endotracheal tube in a generally J-shaped configuration. This has two significant disadvantages. Firstly, the insertion of a J-shaped insertion section into a patient's oral cavity can be difficult. A J-shaped insertion section must be tilted backwards and forwards during insertion to insert the distal end, manipulate the patient's anatomy and obtain a good view of the patient's larynx. It is preferable to provide a laryngoscope which can be more readily inserted. Secondly, this arrangement means that, when the endotracheal tube is pushed forward to advance the tube, a resistive force is developed on the superior side of the tube guide where the endotracheal tube bends from being substantially straight to curved, which increases friction. Some embodiments of the present invention aim to provide an insertion section which is easier to insert into a patient and/or which has a tube guide along which an endotracheal tube can be more readily advanced.
Some aspects of the present invention aim to provide an insertion section having a tube guide which is easier to operate, for example because less force is required, than with known insertion sections with tube guides, or to provide improved adjustability.